OPTICAL RECORDING MEDIUM AND OPTICAL RECORDING MEDIUM REPRODUCING METHOD

• Main Authors: OHNO, EIJI, ABE, SHINYA, TOMIYAMA, MORIO, KAWAGUCHI, YUKO
• Format: Patent
• Language: English; Polish
• Published: 30.06.2010
• Subjects: INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; PHYSICS

An optical recording medium which includes a main-information area in which a reflection film (2) is formed on a substrate where a row of pits is formed as main data, and a sub-information area in which disc information is individually recorded as a barcode-like mark extending in a radial direction of the optical recording medium is disclosed. Further, the barcode-like mark is formed by trimming the reflection film partially and forming a plurality of trimmed areas, and in which information is reproduced by irradiating the reflection film with a beam of light, characterized in that the material and thickness of the reflection film are selected such that when information is reproduced with the beam of light having a wavelength 405 nm and an objective lens with a numerical aperture of 0.85, a value of a jitter becomes 6.5% or lower, in the sub-information area, a row of pits or a groove is formed on the substrate, and the track pitch of the row of pits or the groove is 0.24 µm or wider and 0.45 µm or narrower, the track pitch of the row of pits which is formed on the substrate in the main-information area is 0.24 µm or wider and 0.43 µm or narrower, and the shortest pit (11) of the row of pits which is formed on the substrate in the main-information area satisfies the expression: (shortest pit length) x (track pitch) ‰¤ 0.0512 µm 2 .